mpd.c

   1 /*-
   2  * "THE BEER-WARE LICENSE" (Revision 42):
   3  * <tobias.rehbein@web.de> wrote this file. As long as you retain this notice
   4  * you can do whatever you want with this stuff. If we meet some day, and you
   5  * think this stuff is worth it, you can buy me a beer in return.
   6  *                                                              Tobias Rehbein
   7  */
   8
   9 #include <assert.h>
  10 #include <err.h>
  11 #include <iconv.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include <time.h>
  16 #include <sysexits.h>
  17
  18 #include <mpd/connection.h>
  19 #include <mpd/error.h>
  20 #include <mpd/player.h>
  21 #include <mpd/song.h>
  22 #include <mpd/status.h>
  23 #include <mpd/tag.h>
  24
  25 #include "buffers.h"
  26 #include "mpd.h"
  27
  28 enum {
  29         SLEEP = 5,
  30 };
  31
  32 const char     *NOTAVAILABLE = "n/a";
  33 const char     *NOARTIST = "unknown artist";
  34 const char     *NOTITLE = "unknown title";
  35
  36 struct mpd_context {
  37         struct mpd_connection *conn;
  38         char            mpd_utf[MPD_BUFFLEN];
  39         char            mpd_str[MPD_BUFFLEN];
  40         iconv_t         cd;
  41         time_t          last;
  42 };
  43
  44 struct mpd_context *
  45 mpd_context_open()
  46 {
  47         struct mpd_context *ctx;
  48
  49         if ((ctx = malloc(sizeof(*ctx))) == NULL)
  50                 err(EX_SOFTWARE, "malloc(%d) mpd_context", sizeof(*ctx));
  51
  52         if ((ctx->cd = iconv_open("", "UTF-8")) == (iconv_t) (-1))
  53                 err(EX_SOFTWARE, "iconv_open");
  54
  55         ctx->conn = NULL;
  56         ctx->mpd_str[0] = '\0';
  57         ctx->mpd_utf[0] = '\0';
  58         ctx->last = time(NULL) - SLEEP;
  59
  60         return (ctx);
  61 }
  62
  63 void
  64 mpd_context_close(struct mpd_context *ctx)
  65 {
  66         assert(ctx != NULL);
  67
  68         if (iconv_close(ctx->cd) == -1)
  69                 err(EX_SOFTWARE, "iconv_close");
  70
  71         if (ctx->conn != NULL)
  72                 mpd_connection_free(ctx->conn);
  73
  74         free(ctx);
  75 }
  76
  77 char           *
  78 mpd_str(struct mpd_context *ctx)
  79 {
  80         struct mpd_song *song = NULL;
  81         struct mpd_status *status = NULL;
  82         const char     *artist, *title;
  83         char           *in, *out;
  84         size_t          inleft, outleft;
  85         time_t          now;
  86
  87         assert(ctx != NULL);
  88
  89         now = time(NULL);
  90         if ((now - ctx->last) < SLEEP)
  91                 goto exit;
  92         ctx->last = now;
  93
  94         if (ctx->conn == NULL) {
  95                 if ((ctx->conn = mpd_connection_new(NULL, 0, 0)) == NULL) {
  96                         warnx("mpd_connection_new");
  97                         strncpy(ctx->mpd_str, NOTAVAILABLE, sizeof(ctx->mpd_str) - 1);
  98                         ctx->mpd_str[sizeof(ctx->mpd_str) - 1] = '\0';
  99                         goto exit;
 100                 }
 101         }
 102         assert(ctx->conn != NULL);
 103
 104         if ((status = mpd_run_status(ctx->conn)) == NULL) {
 105                 warnx("mpd_run_status: %s", mpd_connection_get_error_message(ctx->conn));
 106                 strncpy(ctx->mpd_str, NOTAVAILABLE, sizeof(ctx->mpd_str) - 1);
 107                 ctx->mpd_str[sizeof(ctx->mpd_str) - 1] = '\0';
 108
 109                 mpd_connection_free(ctx->conn);
 110                 ctx->conn = NULL;
 111                 goto exit;
 112         }
 113         if (mpd_status_get_state(status) != MPD_STATE_PLAY) {
 114                 ctx->mpd_str[0] = '\0';
 115                 goto exit;
 116         }
 117         if ((song = mpd_run_current_song(ctx->conn)) == NULL) {
 118                 strncpy(ctx->mpd_str, NOTAVAILABLE, sizeof(ctx->mpd_str) - 1);
 119                 ctx->mpd_str[sizeof(ctx->mpd_str) - 1] = '\0';
 120                 goto exit;
 121         }
 122         if ((artist = mpd_song_get_tag(song, MPD_TAG_ARTIST, 0)) == NULL)
 123                 artist = NOARTIST;
 124
 125         if ((title = mpd_song_get_tag(song, MPD_TAG_TITLE, 0)) == NULL)
 126                 title = NOTITLE;
 127
 128         inleft = snprintf(ctx->mpd_utf, sizeof(ctx->mpd_utf), "%s - %s", artist, title);
 129
 130         inleft = inleft < sizeof(ctx->mpd_utf) ? inleft : (sizeof(ctx->mpd_utf) - 1);
 131         outleft = sizeof(ctx->mpd_str);
 132         in = (char *)ctx->mpd_utf;
 133         out = (char *)ctx->mpd_str;
 134
 135         if (iconv(ctx->cd, NULL, NULL, &out, &outleft) == (size_t) (-1))
 136                 err(EX_SOFTWARE, "iconv");
 137         while (inleft > 0) {
 138                 if (iconv(ctx->cd, (const char **)&in, &inleft, &out, &outleft) == (size_t) (-1)) {
 139                         if (errno == E2BIG)
 140                                 break;
 141                 }
 142         }
 143         *out = '\0';
 144
 145 exit:
 146         if (song != NULL)
 147                 mpd_song_free(song);
 148         if (status != NULL)
 149                 mpd_status_free(status);
 150
 151         return (ctx->mpd_str);
 152 }